When the apocalypse strikes, you probably won't have access to the Internet. That means no Google, no Wikipedia, and, if you haven't prepared, no cheat sheet to help you through the tough times. Here are a few books you might want to have on hand in case the worst happens. Just remember to keep a back-up pair of glasses in your emergency kit.

This set of books doesn't assume any particular type of apocalypse — you'd need to shift your approach for an atomic apocalypse, a pandemic, or supervolcanos ripping the continents apart. You might also want more texts on specific skills like blacksmithing, toolmaking, and woodworking. But these books cover the very basics: outdoor survival, food, medical care, and shelter, with some additional homesteading information, as well as the text-based building blocks to rebuild civilization. Any preppers out there, please share your go-to texts in the comments.

General Survival and Homesteading:

SAS Survival Handbook: The Ultimate Guide to Surviving Anywhere, by John "Lofty" Wiseman: For 26 years, Wiseman served as a member of the British Army's elite Special Air Service. The SAS is trained for survival in various regions, and under a number of conditions. SAS Survival Handbook includes all the basics of survival — from setting up camp and proper fire making to making tools and navigating by the sun and stars. It even considers a range of potential disasters you may have to survive — avalanches, tornados, earthquakes, even the aftermath of a nuclear disaster.

US Army Field Survival: Another military survival text for surviving in a number of situations, this manual explains the psychology of survival and preparation procedures, in addition to maintaining hygiene, crafting a makeshift shelter, and making water potable. Like the SAS Handbook, this version is edited for civilian use. It also comes as a free PDF download.

Foxfire Books: Foxfire Magazine actually started as a sociological project to share aspects Appalachian culture. But the books, which collect articles from the magazine as well as items that never made it into the original periodical, have become the go-to guide for many do-it-yourselfers. There is a lot of superstition and folklore between those pages, but the books are rich with information on slaughtering animals, preserving food, making soap, setting bird and rabbit traps, knife making, blacksmithing, moonshining, home remedies, and more. You can buy the books from the Foxfire Museum Gift Shop.

The Encyclopedia of Country Living by Carla Emery: Modern homesteaders swear by this back-to-the-land guide. If you manage to set yourself up on a little plot of land, this book will explain how to make yourself comfortable by growing flax and making your own linen, foraging for wild rice, making acorn flour, keeping bees, making dandelion root or chicory coffee, raising rabbits, building barns and fences, pressing oil from seeds, tanning hides, even burying your dead.

There are a lot of great, comprehensive medical references out there. A lot of preppers recommend getting your hands on a copy of the Merck Manual, and you should find a good illustrated medical dictionary, a drug reference, and an anatomy and physiology text. The WHO also puts out lists of essential medications to have on hand for adults and children. Also, you should consider picking up a basic veterinary guide, especially if you plan on keeping domestic animals. But here are a few references for more basic medical care:

Where There is No Doctor: This reference, published by the Hesperian Foundation, is used the whole world over. It's distributed by the Peace Corps, and while its emphasis is largely on the third world, it contains information on treating a number of diseases and ailments without medical expertise. If you need to set a fracture or deliver a baby, this is the reference for you. Hesperian also offers a number of other health-related titles, including Where There is No Dentist, Where Women Have No Doctor, Water for Life, and Cleanliness and Sanitation, all of which are available for purchase or as free downloads. If you're looking for other basic low-tech medical guides, check out Survival and Austere Medicine: An introduction and the US Department of Defense's Special Operations Forces Medical Handbook, both of which are available as free downloads.

Ditch Medicine : Advanced Field Procedures for Emergencies by Hugh L. Coffee: This text gets more advanced than Where There is No Doctor, and you'll probably want at least an EMT certification before you attempt man of the procedures in this book. But if you need a reference on performing minor surgery, perform an amputation, or treat anaphylactic shock, this is your book. Just make sure you'll have the necessary supplies on hand, since a lot of the procedures require catheters, IVs, and surgical tools.

A Field Guide to Medicinal Plants and Herbs: Of Eastern and Central North America (Peterson Field Guide): Obviously, you should get yourself a guide that focuses on your particular region of the world, but the Peterson Field Guides are quite useful if there's one for your area. Make sure you get your hands on a well vetted guide that contains color photographs or illustrations of medicinal plants. A good guide can help you find the right plants to kill pain, alleviate depression, reduce prostate swelling, stop bleeding, and settle stomachs — while also warning you of similar looking, but toxic, plants.

Peterson Field Guides to Edible Wild Plants: The handy thing about the Peterson Field Guides is that, if you live in North America, there are specific guides for specific regions, so you can have a tailored guide for the spot where you live. Plus, the guides are illustrated and easy to follow.

The New Self-Sufficient Gardener by John Seymour: The homesteading books will give you some information on growing and preserving your own fruits and vegetables, but you'll want at least one volume that gives you a complete overview on self-sufficient farming — from preparing the soil to pickling your vegetables.

The Building Blocks to Rebuild Civilization: Once you've got the basics under control, you may want to help put the world back together. The CD3WD project was launched by programmer Alex Weir to spur development in the third world. Currently, the project has accumulated roughly 4 DVDs worth of information, covering things like agriculture, food processing, water filtration, and irrigation in more depth, as well things like construction of basic tools, vehicles, and more complex buildings, and moving into things like economics, metalwork, electrical work, the formation of biodiesel, and addressing gender inequalities. It's information that could help you rebuild and infrastructure and begin the long, slow trek back to civilization. [via Lifehacker]

Should I get hard copies or digital? When this topic was suggested to us, the request was for books that folks could keep on their tablet computers. This lead to a question: Is it really a good idea to keep your survival books on a tablet? Books are heavy to lug around, but they also don't depend on electricity. (Edit: Or flash memory, as is mentioned in the comments.) But the good news is, if you can charge your tablet, it uses considerably less energy than other digital storage devices, like full computers. This Tekzilla episode outlines the different ways to charge your devices in an emergency.

If you do decide to store your survival books on your tablet, make sure you're storing actual digital files and not just access to those files. The Amazon Cloud will likely not save you in the post-apocalypse. And it isn't a terrible idea to have physical copies — at least as a backup.